$_SERVER variables in method

Seems not to work!
I'd tried to use server variables inside my method. and they're not set in.
my code:

echo "server vars: " . $_SERVER['REMOTE_ADDR'] . " " . $PHP_SELF;

returns
server vars:

means nothing!!!
how it is possible solve this problem?
Thanks.

You have to declare them as a global variables:

global $_SERVER;
global $PHP_SELF;

Not entirely true, $SERVER is a superglobal (see http://us2.php.net/manual/en/language.variables.predefined.php) and is global in all scopes, even inside a function, assuming your version of php is >= 4.1. If it isn't, $SERVER doesn't exist.